Casing landing, packing and blowout prevention assembly



Sept. 19, 19330 0! K, s s 1,927 1@ CASING LANDING, PACKING AND BLOW-OUT PREVENTION ASSEMBLY Filed Sept. 16, 1930 l i W V 1 l 32 Inventors W ML 9 W Patented Sept. 19, 1933 iTED STATES GASING LANDING,

PACKING AND BLOW- OUT PREVENTION ASSEMBLY Oscar Kezer Stephens, San Gabriel, Calif.

Application September 16, 1930 Serial No. 482,181

19 Claims.

This invention relates to casing head apparatus.

In drilling oil wells it is customary to case or line the hole with several diiferent sizes of pipe or casing, starting at the top with a relatively large size and employing smaller sizes in a telescopic manner until reaching the proper depth, each size being cemented off at its lower end.

As each size of casing must reach to the top of the well, it will be easily seen that some means of suspending the casing must be provided.

During the process of drilling, gas or fluid under high pressure is frequently encountered. The uncontrolled flow of this gas or fluid up through one or more of the well casings often causes serious damage, and the loss of life. Under the present method of suspending casing, it is customary to provide each individual casing with a combination landing and packing device.

In the present practice, and with the present design of landing and packing devices, it is necessary to let the cement on the casing properly set before the casing can be suspended, this because of the fact that it is necessary to slack off and disengage the elevating apparatus from the top of the casing before the suspending and packing device can be passed down over the casing, and it will be readily seen that the cement on the lower end of the casing may be damaged and that the casing itself may be injured by this operation.

One object of my present invention is to provide a simple landing and packing device so constructed that it may be used as a common landing and packing device on all sizes of casing now in general use as water strings, and so constructed that the casing may be suspended and packed without the necessity of changing the amount of tension on the top of the casing, this being possible with this device on all succeeding strings of casing in a well after the first water string is set because of the fact that a complete assembly of landing and packing heads may be placed in position and secured together when the first water string is set, consequently they are in place and ready to receive the slips as each string of casing is set.

The fact that these heads may be placed in position when the first water string is set is made possible by the identity of form of the heads, each one having a like size, shape and design, and the inside diameter being the same for all sizes of easing.

Another object of this invention is to provide a casing head of such construction that it may be used above any size of easing as a blowout preventer, it having an internal opening of a size and degree of taper to correspond with the opening in the landing and packing heads, making it possible to use it as a slip spider when running casing; as a blowout preventer when drilling or running casing or as a production head when producing a well.

In the embodiment of in the following specification, the apparatus includes a bottom base plate and a plurality of landing and packing heads of like size, shape and features of construction placed one upon the other, and with the lowermost resting upon the base plate and the uppermost to be topped by a casing head; and one of the objects of this invention is to provide means for securing these parts together in a pressure holding assembly.

Further objects of this invention will appear hereinafter.

The invention consists in the novel parts and combinations of parts to be described hereinafter, all of which combine to produce a radical improvement over the landing and packing devices now in use.

A preferred embodiment of the invention is described in the following specification while the broad scope of the invention is pointed out in the appended claims.

In the drawing- Figure 1 is a vertical central section through a casing head apparatus, embodying my invention, showing a number of stacked spiders, or collars, forming a casing head; this view illustrates the use of the base plate, the intermediate spiders, the casing head proper which I term a service head, the blowout preventer plug and the bolts for securing the device together.

Figure 2 is a side elevation of a drilling fluid conductor, the bottom of which is received while drilling, on the packing ring carried in the top of the service head.

In practicing the invention, I provide a bottom collar or base collar, or spider, 1, which is constructed to rest upon the concrete cellar floor 2, at the mouth of the well. This collar is provided with means such as a tapering opening 3, into which the top of the surface casing 4 may be received and welded.

This surface casing 4, is, of course, of a comparatively large size to accommodate a drill bit of a large size, this being necessary in the upper surfaces of the earth because of the frequency of boulders, etc.

This surface casing 4 is generally self-supporting because of the fact that it is cemented for its entire length and that portion of it from the cellar floor up to the settling ditch may be used as a drilling fluid conductor, until the first water string is set.

After reaching the proper depth it becomes necessary to set the first water string or casing 5.

The casing 5 may be made up and run into the well to the proper depth after which it would be cemented in. The cement would be allowed to the invention disclosed set after which the elevating apparatus may be disengaged from the upper end of the casing 5 and the surface casing 4 may be cut oil by means of a torch a few inches above the cellar floor 2 and the short piece of the casing 4 maybe stripped up over the casing 5, after which the collar 1 may be passed down over the casing 5 and placed around the top of the casing a to which it may be welded.

After this operation is completed the landing collar or head 6 may be passed down over the casing 5 and placed upon the collar 1, after which the elevating apparatus may be again attached to the top of the casing 5 and a desirable amount of strain maintained in the casing 5 while the slips 7 are properly set, after which the elevating apparatus may be slacked off and the casing 5 is then suspended by the slips 7.

The casing 5 may then be cut ofl at a point a few inches above the slips 7 and a circular bafile plate 8 introduced. This baffle has a central opening of an inside diameter to approximately equal the outside diameter of the casing 5 and an outside diameter to approximately equal the inside diameter of the landing head 6 at the point 9. This baflle may be passed down over the end of casing 5 and set upon a circumferential shoulder 10, which I format this level in the collar 8.

This baflle plate 8 is provided with a central opening with a tapering portion or conical bore 11 into which the top portion of the casing 5 may be belied or expanded with the aid of a gas torch, after which the top of the casing 5 may be welded to the bathe plate 8 at the point 12. This weld would, of course, extend entirely around the circumference, and should be gas tight.

It will be readily seen by an experienced operator that there is a possibility for a gas or fluid pressure to accumulate below this bafile plate 8 and consequently a lifting force may be exerted by the pressure under side of the bafile plate 8 and for that reason I have provided a circumferential key 13 which is preferably made up of a number of sections to make its insertion possible.

This circumferential key 13 is inserted in a circumferential recess 14 that I form on the inner face of the collar, and acts as a stop against the upward movement of the bafile plate 8. After this key 13 is properly placed, an electric welding torch is used to make a circumferential weld at the points 15 and 16, and the ends of the key are welded together thus forming a gas, or fluid, seal at these points.

A port 17 is provided for the purpose of relieving or increasing fluid or gas pressure between the two strings of easing a and 5 and these ports pass up through the bottom of the collar and out through its side, where threads are provided to receive pipe fittings for their proper connection to the fluid pumps commonly used on drilling wells.

The operator of the well should then decide how many strings of easing he will employ to complete the well. Should he decide that he will need to set three more strings of casing, he may at this point secure three more landing heads and place them upon the first, one above the other.

It should be explained at this point that each head is provided with a packing ring groove 18 in its upper face and a packing ring seat 19 in its lower face to act as a pressure seal between the respective heads when secured together.

When the necessary number of landing heads 6 have been properly assembled, one above the other, the next procedure is to secure a casing head or as it will be called in this description, a

service head 20, and install it on the upper face of the top landing head 21. This service head 20 is provided with a packing ring groove 22 in its upper face and a packing ring seat 23 in its lower face and they correspond in size, shape and design with those in the landing heads, making it possible to form a pressure sealing circumferenrial Joint with the landing head 21 directly be- I have provided the service head 20 with an integral external circumferential flange 2a through which I have provided a plurality of vertical holes or slots 25 through which may be passed the bolts 26.provided for clping the service head and the collars to the base 1.

The base plate 1 is made with a larger outside diameter than the landing heads and the projecting portion 27 of this base plate is provided with a plurality of threaded vertical openings 28 for the purpose of receiving the lower ends of the bolts 26 which are provided with threads 29. The bolts 26 are made secure in the base plate 1 after which nuts 30 are screwed onto the threaded upper end of the bolts 26 and these nuts 30 are tightened down securely on the flange 24 thus securing the complete assembly together.

It then being desirable to go still deeper with the well, some means must be provided to con-- duct the drilling fluid from the service head to the settling ditch.

It has been customary in the past with other types of casing head apparatus to provide a port of large ensions in the wall of the service head. This port must be valved by a valve of suitable size and it is the experience of most operators that this valve being in the open position while drilling, becomes sanded up and will not work properly on sudden demand as, for instance, when the blowout preventer is set and a gas or fluid pressure builds up in the casing.

For that reason, I have provided the conductor pipe 31 which is a piece of casing 31, the bottom of which may be received by the circumferential packing ring groove 22. The fluid pressure in this conductor is very low and leakage of the drilling fluid at the point 32 is prevented by in= serting a ring of packing in the groove 22 before setting the conductor 31 in position.

The conductor may be secured to the service head circumferential flange 33 by means of small bolts 34 which are passed through the ears 35 and thence through the circumferential flange 33.

To. conduct the drilling fluid from this conductor to the settling ditch I have provided the internally threaded collar 38 which may receive a pipe of proper size to conduct the drilling'fluid to the settling ditch.

This conductor makes it unnecessary to use a port through the wall of the service head 20 for ordinary drilling conditions but it frequentlyhappens that blow out of gas or fluid from the wall may occur, in which case it would be desirable to set a blowout preventer plug to stop the flow. For that reason, I have provided the port 37 which is a port of comparatively small size but entirely ample for releasing or increasing the pressure in the well. I provide a plurality of these ports 37 in the service head'21 which are provided with threads 38 for receiving pipe fittings such as 39 for their proper connection to fluid pumps or settling ditch.

After reaching the proper depth, it becomes necessary to set another string of casing and so the drilling tools are removed from the well and his the casing 40 is made up and run into the well, let

and the cement is properly placed around its lower end, the top of the casing 40 being suspended by the elevating apparatus.

It is then only necessary to remove the nuts from the bolts 26 and by means of the cat line, the landing heads 41 and 42, together with the service head 20 and the conductor pipe 31 are elevated a few inches and the slips 43 are placed in the landing head 44 and properly seated in the tapering internal circumferential seat 45 which I have provided for that purpose.

The weight of the casing 40 may then be slacked off and the slips 43 will receive and hold it, after which the casing 40 may be cut oil a few inches, above the slips 43 and the short piece expanded down.

The baiile plate properly set, keyed 46 may then be placed and and welded as was baflie plate 8, after which the heads 41, 42 and 20, together with the conductor 31, may be replaced and secured as before, and should it be desirable to change to a different size of drill pipe, that operation may proceed at once.

The drilling may proceed as soon as desirable and after reaching a proper depth, it becomes necessary to set another string of casing 47.

This string 4'1 is made up and properly cemented, its top end being supported by the elevating apparatus during this process, after which the nuts 30 may be removed from the bolts 26 and the heads 42 and 20 together with the conductor 31 may be raised a few inches and the slips 48 may be properly placed and seated in the internal tapering circumferential slip seat 49, and around the casing 47. This operation being properly completed the elevating apparatus may be slacked ofl, allowing the casing 4''! to be held securely by the slips 48.

The casing 4'7 may then be cut oil a few inches above the slips 48 and the baflle plate 50 may be properly placed, keyed and welded as was bailie plate 8, after which the heads 42 and 20, together with the conductor 31 may be replaced and secured as before, after which drilling may proceed as soon as desirable.

As before explained, blowouts may be expected on an oil well, in the process of drilling, and several types of blowout prevention plugs have been developed for the purpose of packing around the drill pipe and stopping the gas or fluid from the well. These plugs have all had their disadvantages and I have constructed the plug about to be described, with the idea of overcoming these disadvantages.

As shown in Figure 1, this plug is substantially of a conical cross-section and is diametrically divided. The two halves are hinged together and a latch is provided to latch the two together. It is provided with a central vertical opening of a diameter to approximately equal the outside diameter of the drill pipe or tubing 52, and should its use be necessary, it may be latched around the drill pipe or tubing 52 and inserted into the conical seat 53 of the service head 20. The top portion 55 and the bottom portion 54 of the plug are circular metal plates having an intermediate disc of a compressible material 56.

The top plate is provided with a plurality of pivotally mounted dogs 57, the free ends 58 of which are received in a circumferential groove 59 when the plug is properly seated inthe opening 53. a

These dogs 57 being pivotally mounted on the top plate 55 by their pivot pins 60, resist any upward movement of the plug, and to provide against leakage around or through the plug, some means must be provided to expand the compressible material 56 in a radial direction.

For this purpose, I have provided a plurality of bolts 61 which are threaded on their lower ends 62 and are received by threaded openings in the plate 54. They extend through vertical openings in the compressible material 56, and project up through vertical openings in the cover plate of the plug. 1

The upper ends of these bolts 61 are provided with threads which receive nuts 63 which may be tightened against the plate 55 thus drawing the plate 54 up tightly against the compressible material 56, which will be forced to expand in a radial direction, which action will effect a pressure resisting seal around the pipe 52 and within the seat 53.

The pipe 52 may be worked up and down through the plug to keep the drill bit from becoming "frozen in the hole, and the pressure in the. well may be overcome by the use of cir= culating fluid as is customary, the port 39 being provided as a circulation port.

When the blowout has been overcome, it is only necessary to loosen the bolts 61 and disengage the dogs 57 after which the plug may be withdrawn and drilling may proceed.

After reaching the proper depth which we will say is the upper layer of the oil sand, it is necessary to set another string of casing 64. This string 64 is run in and properly cemented and with the elevating apparatus suspending the casing 64, the nuts 30 may be removed from the bolts 26 and the head 20 may be elevated a few inches by means of a cat line after which the slips 65, may be placed in the slip seat 66 of the head 42 and around the casing 64. The elevating apparatus on the casing 64 may then be slacked oil, putting the weightv on the slips 65, after which the casing 64 may be cut oil a few inches above the slips 65 and the baflle plate 6'7 may then be properly placed over the top of the casing 64 after which it is keyed and welded as was bailie plate 8.

The service head 20 and conductor 31 are then replacedon top of the head 42 and properly secured by the bolts 26 and nuts 30 and drilling into the oil sand may proceed as soon as desirable.

After reaching the desired depth into the oil sand, a liner may be set in the bottom of the hole'if desirable, or as some operators do, the well may be brought in without the use of a perforated liner, in which case a string of tubing may be desirable. This tubing 52 may be made 1 up and run in and suspended by means of a top collar 68 which may be seated upon the blowout preventer plug which is of course properly seated and secured inthe service head 20.

It being now desirable to produce the well, the production assembly, which is not a part of this invention, may be secured to the upper face of the service head flange 33 by means of a plurality of bolts 69 which are received by a plurality of vertical holes in the integral circumferential Til-C flange 33 of the service head 20.

Production of the well may be achieved by swabbing or pumping.

I wish to point out the fact that the tapering seat 53 in the service head 20 is of the same diameter and degree of taper as that in the landing heads 6, 44, 41' and 42, making it possible to use the same slips in the service head for running casing which would eventually be used to land the casing.

The slips 7, 43, etc., referred to above are of the usual segmental form. There is, of course, sumcient clearance between adjacent slips to enable them to perform their functions.

. Having described my invention what I claim 1. In a owing head apparatus, the combination of a plurality of stacked spiders, having bores respectively of substantially the same di-- ameter and taper, slips oi difierent thickness corresponding to the difierent spiders to cooperate with the same to engage well casings of different diameters, with the largest diameter casing located at the lowest spider of the stack, a baffle ring received in each spider above its slips to be connected to the corresponding casing, and means associated with each bafie for sealing the outer edge of the same to the spider.

2. In a casing head apparatus, the combination of a plurality oi. stacked spiders, having bores respectively of substantially the same diameter and taper, slips of difierent thickness corresponding to the different spiders to cooperate with the same to engage well casings of different diameters, with the largest diameter casing lo cated at the lowest spider of the stack, a bame ring received in each spider above its slips to be connected to the corresponding casing, and means associated with each baiile for sealing the outer edge of the same to the spider, each of said spiders having a port on its underside and emerging on its side wall to receive a pipe connection, and means between the spiders near their peripheries for packing on the spaces between them.

3. In a casing head apparatus, the combination of a plurality of stacked spiders, having bores respectively of substantially the same diameter and taper, slips of diiierent thickness corresponding to the diiierent spiders to cooperate with the same to engage well casings oi different diameters, with the largest diameter casing located at the lowest spider of the stack, a baiile ring received in each spider above its slips to be connected to the corresponding casing, and means associated with each bafile for sealing the outer edge of the same to the spider, each of said spiders having a port on its underside and emerging on its side wall to receive a pipe connection, and means between the spiders near their peripheries for packing off the spaces between tnem, a service head seating on the uppermost spider, and a base ring supporting the lowermost spider, and tie rods connecting the service head and the base ring and securing the spiders together.

4. In a casing head apparatus, the combination of a plurality of stacked spiders, having bores respectively of substantially the same diameter and taper, slips of difierent thickness corresponding to the difierent spiders to cooperate with the same to engage well casings of different diameters, with the largest diameter casing located at the lowest spider of the stack, a bafile ring beceived in each spider above its slips to be connected to the corresponding casing, means associated with each baffle for sealing the outer edge of the same to the spider, each of said spiders having a port on its underside and emerging on its side wall to receive a pipe connection, means between the spiders near their peripheries for packing off the spaces between them, a service head seating on the uppermost spider, a base ring supporting the lowermost spider, and tie rods connecting the service head and the base ring and securing the spiders together, and a well, a plurality of stacked spiders having bores seamen casing of relatively large diameter welded to the inner face of the base ring.

5. In a casing head apparatus for wells, the combination of a plurality oi well casings of progressively reduced diameter projecting from the respectively of substantially the same diameter and taper, slips of difi'erent thickness corresponding to the different spiders to cooperate with the same to engage the casings of difierent diameters, a bafiie ring corresponding to each casing and received in its correspondinging spider above its slips and welded to the mouth of its corresponding casing, and sealing means for sealing the outer edge of each baiiie to its corresponding spider.

6. In a casing head apparatus, the combina-- tion of a plurality of stacked spiders having bores respectivelypi substantially the same diameter and taper,,slips of difierent thicknesses corresponding to the different spiders and received within the same for clamping casings of dififerent diameters, a baiile having a conical inner opening into which the mouth of its corresponding casing can be expanded, each spider having an annular shoulder, and a sealing ring corresponding to each spider to be sealed at its inner edge to the baiile and with its outer edge projecting under the shoulder and sealed to the same.

7. In a casing head apparatus, the combination of a plurality of stacked spiders having bores respectively of substantially the same diameter and taper, slips of different thicknesses corresponding to the difierent spiders and received within the same for clamping casings of difierent diameters, a baffle having a conical inner opening into which the mouth of its corresponding casing can be expanded, each spider having an annular shoulder on the inner face of its well, a sealing ring corresponding to each spider resting on the upper face of its corresponding bafie and projecting under the said annular shoulder, and welded to the said shoulder and the corresponding baflle.

8. In a casing head apparatus, the combination of a plurality of stacked spiders having bores respectively of substantially the same diameter and taper, slips of different thicknesses corresponding to the different spiders and received within the same for clamping casings of different diameters, a'bafile having a conical inner opening into which the mouth of its corresponding casing can be expanded, each spider having an annular shoulder, and a sealing ring corresponding to each spider formed in sections resting on its corresponding baflle plate and projecting under the said shoulder of the spider, and having a gastight welded connection to the spider and to the baille.

9. In a casing head apparatus, the combination 5 of a plurality of stacked spiders, having taper bores, slips corresponding to the diiferent spiders to cooperate with the same to engage well casings of difierent diameters, with the largest diameter casing located at the lower spider of the stack, a 14(1 bafile ring received in each spider above its slips to be connected to the corresponding casing, and means associated with each baflle for sealing the outer edge of the same to the spider.

10. In a casing head apparatus, the combination of a plurality of stacked spiders, having taper bores, slips corresponding to the difierent spiders to cooperate with the same to engage well casings of diiierent diameters, with the largest diameter casing located at the lowest spider of the stack, 154) a bafile ring received in each spid r above its slips to be connected to the correspon ing casing, and means associated with each baffle for sealing the outer edge of the same to the spider, each of said spiders having a port on its underside and emerging on its side wall to receive a pipe connection, and means between the spiders near their peripheries for packing 01f the spaces between them.

11. In a casing head apparatus, the combination of a plurality of stacked spiders, having taper bores, slips corresponding to the different spiders to cooperate with the same to engage well casings of different diameters, with the largest diameter casing located at the lowest spider of the stack, a bailie ring received in each spider above its slips to be connected to the corresponding casing, means associated with each baflie for sealing the outer edge of the same to the spider, each of said spiders having a port on its underside and emerging on its side wall to receive a pipe connection, means between the spiders near their peripheries for packing off the spaces between them, a service head seating on the uppermost spider, a base ring supporting the lowermost spider, and tie rods connecting the service head and the base ring and securing the spiders together, and a casing of relatively large diameter welded to the inner face of the base ring.

12. In a casing head apparatus for wells, the combination of a plurality of well casings of progressively reduced diameter projecting from the well, a plurality of stacked spiders having taper bores, slips corresponding to the different spiders to cooperate with the same to engage the casings of difierent diameters, a bafile ring corresponding to each casing and received in its corresponding spider above itsslips and welded to the mouth of its corresponding casing, and sealing means for sealing the outer edge of each baflie to its corresponding spider.

13. In a casing head apparatus, the combination of a plurality of stacked spiders having taper bores, slips corresponding to the different spiders and received within the same for clamping casings of different diameters, a baflie having a conical inner opening into which the mouth of its corresponding casing can be expanded, each spider having an annular shoulder, and a sealing ring corresponding to each spider to be sealed at its inner edge to the bafile and with its outer edge projecting under the shoulder and sealed to the same.

14. In a casing head apparatus, the combination of a plurality of stacked spiders having taper bores, slips corresponding to the different spiders and received within the same for clamping casings of different diameters, a bafile having a conical inner opening into which the mouth of 'its corresponding casing can be expanded, each spider having an annular shoulder on the inner face of its wall, a sealing ring corresponding to each spider resting on the upper face of its corresponding baffle and projecting under the said annular shoulder, and welded to the said shoulder and the corresponding baffle.

15. A casing head comprising a body having a tapered slip slideway, slips to hold casing mounted on said slideway, a casing collar mounted on said body, means detachably securing said collar and body together, said collar having an internal shoulder inclined outwardly and facing upwardly, casing held by said slips and having an initial slip joint connection with said collar with the upper end belled and welded to said collar to form a seal.

16. A casing head comprising a body, gripping means supported thereby to grip a casing, a casing collar mounted on said body above said gripping means, means securing said collar and body together, casing held by said gripping means and initially forming a slip joint connection with said collar with the upper end of said casing welded to said collar to form-a seal.

17. In a device for the purpose set forth, a pipe let into an oil well and having its upper end projecting above the ground surface, a concrete foundation body arranged around the said end of the pipe, other pipes of smaller diameters to be received one in the other and in the last mentioned pipe, spiders of like shape, size and design to be attached to the last mentioned pipes by means of slips and resting one upon the other and the lowermost spider resting upon a metal collar and the central opening of each spider being provided with an annular depression, the lower shoulder of which may receive the outer periphery of a bafiie plate and the upper shoulder of the said annular depression being designed to.

receive and act as a retainer or stop for a trisected circumferential key the lower face of which may be received upon the upper face of the above mentioned baflle plate for. the purpose set forth.

18. In a device for the purpose set forth, a pipe let into an oil well and having its upper end projecting above the ground surface, a concrete foundation body arranged around'the said end of the pipe, other pipes of smaller diameters to be received one in the other and in the last mentioned pipe, spiders of like size, shape and design to be attached to the last mentioned pipes by means of slips and resting one upon the other and the lowermost spider resting upon a metal collar and the central opening of each spider being provided with an annular depression or keyway to receive a trisected circumferential key to act as a retainer against the upward movement of an annular bailie plate the said baflie plate being provided with an upwardly extending, integral neck portion the central opening of which is of a diameter to approximately equal the outside diameter of the above mentioned pipe and being provided with a tapering annular depression into which the top portion of the above mentioned pipe may be belled and welded thereto for the purpose set forth.

19. In a device for the purpose set forth, a pipe let into an oilwell, and having its upper end projecting above the ground surface, a concrete foundation body arranged around the said end of the pipe, other pipes of smaller diameters to be received one in the other and in the last mentioned p pe spiders of like size, shape and design to be attached to the last mentioned pipes by means of slips and resting one upon the other and the lowermost spider resting upon a metal collar and the uppermost spider being topped by a service casing head and each of the said spiders and service casing head being provided with threaded ports, said ports being horizontal bores into the outer periphery of the said spiders and service casing head and communicating with approximately vertical bores, said vertical bores communicating with the interior of the assembly at their lower ends.

OSCAR KEZER STEPHENS. 

